Please help?!:/

We titrate a solution containing calcium ions (Ca2+), V=100 mL, with EDTA solution 0.1 M. The end point is determined at 10 mL. What is the equivalent point of the process? Based on the reaction, calculate the total hardness of the sample in mol/L CaCO 3 and mg/L CaCO3. Calculate the content of calcium ions (Ca2+) as [Ca2+] and the contents [EDTA ] and [Ca2+-EDTA ] after adding 5mL of titrant. Explain based on reactions.

So far I've tried: nEDTA=(0.1*0.01)=0.001mol, nCaCO3=0.001mol (reaction 1:1)

Conversion: mCaCO3=n*molar mass=0.10009g then mg/L=mCaCO3*VH2O*1000mg/g=1000,9mg/L

Then, after adding 5mL of titrant: cCaCO3=molesCa2+/VH2O=0.0005*0.105L=0.00475mol/L,

For the equivalent point, I thought of using cAvA=cBvB => (0.1)(0.1)=cB(0.01) but Im not sure.

For EDTA concentration" (10-5mL)=> nEDTA/vH2O=(0.1mol/L * 0.01L * 0.0005mol)/(0.01L-0.005L)=0.1mol/L

Ca-EDTA: 0.1mol/L - 0.00476mol/L = 0.09524mol/L

(Not sure) should volume after adding be 100mL+5mL?

Any help is MUCH appreciated. Thank you.